1. The Field of the Invention
The present invention is in the field of medical electronics, and more specifically relates to an intelligent computer calculator for collecting, displaying, and recording data that relates to a patient's fluid balance during surgery, and to the status of secured surgical items used during surgery, such as sponges and needles. The computer calculator not only records and displays the number of sponges utilized in the patient during surgery, but it can also translate the weight of sponges into fluid volume lost by a patient, and it can provide a manual mode by which additional fluid loss through abdominal, chest, or bladder drainage may be added to blood loss to obtain an accurate estimate of the entire fluid loss of a patient during a procedure. Because it is standard practice in an operating room to count sponges during surgery, the computer calculator can also automatically count, display, and a record sponges as they are discarded from the patient. Other secured items such as needles may also be manually calculated, displayed, and recorded on the computer in single, multiple or predetermined multiple suture packages. The computer can provide an audible tone to inform the operating room associates of excessive fluid loss, and it can provide a printed or other tangible copy of each transaction involving fluid loss, sponges, needles, and other secured items monitored by the invention.
2. The Prior Art
In U.S. Pat. No. 4,295,537 filed Oct. 20, 1981, for Sponge Measuring Device by McAvinn et al., there is described a device that attempts to weigh and count surgical sponges. The device provides a receptacle for placement of the sponges and a housing device for collection of the sponges to facilitate the sponge count at the end of the procedure. The device is designed to allow the operator to weigh the plurality of collected sponges and to subtract the weight of any equal number of dry sponges to estimate the amount of blood loss in the wetted, discarded sponges.
A counting and weight collector for surgical sponges was also described in U.S. Pat. No. 3,367,431 filed Feb. 6, 1968 by Dorothy H. Prindle Baker for Surgical Sponge Collector with Means for counting and Weighing Sponges. The device provided a cabinet with receiver slot, a counter on the cabinet, a light source in the cabinet projecting a beam across the slot, and a light-responsive device that activated the counter when a sponge passed through the slot. The invention provided a continuous and visible indication of the number of sponges and the total weight.
In the U.S. Pat. No. 4,422,548 filed Dec. 27, 1983 for sponge measuring device by Cheesman et al., there is described a device for counting, weighing, and disposing of soiled surgical sponges. The device provides a receptacle for placement of the sponges, a housing device for collection of sponges, and a scale for weighing the sponges. The device is designed primarily to provide a system for counting, weighing, and disposing of soiled surgical sponges with a minimum of handling by operating room personnel.
The device of Cheesman et al., it provides only the weight of soiled sponges. It is more practical and accurate to utilize the invention which includes a device that provides a means for electronically converting the weight of the soiled sponge into volume of blood contained in the soiled sponge. This is more accurate and practical because volume of blood loss is the determining factor for replacement of blood or fluid to the patient. The Cheesman et al., device does not convert the weight of the sponge into volume of cubic centimeters of blood loss.
Urine, like blood, is also a volumetric fluid loss, and is more accurately accounted for when the loss is measured volumetrically, in cubic centimeters rather than in grams of weight. The Cheesman et al. device provides no capability for electronic conversion of urine weight or blood weight into parameters, and one of ordinary skill in the art is accustomed to dealing with volumetric, cubic centimeter parameters.
The device described by Cheesman et al., also fails to provide the capability to manage information about fluids other than blood, which are of significance during an operating procedure. The capability to enter information about the addition of fluids to the patient, and the deletion of fluids from the patient, is central to the capability of maintaining an accurate electronic assessment of a patient's fluid balance status. The significance and importance of maintaining a current assessment of the patient's fluid balance during a procedure is obvious to anyone of ordinary skill in the art.
U.S. Pat. No. 3,618,836 of Bushnell, et al., there is described a device for encoding containers containing biological samples.
While the Bushnell, et al., device provides a needed service for biological samples handling, it is inadequate and ill-equipped to provide the comprehensive management of data, as provided by the present invention.
The Bushnell, et al., device provides no capability for fluid balance assessment, no capability for soiled sponge handling after recording and counting them, and no capability for a surgeon to obtain electronic data from a floppy disk facility, such as can be provided in the device in the present invention.
The types of collectors-counters demonstrated in the prior art, do not provide the automatic translation of sponge weight into cubic centimeter or mililiters of blood loss. The former devices also make no provision for the addition of other fluids frequently loss during routine surgeries; all such lost fluids must be taken into consideration before blood or fluid replacement therapies are instituted by the physician. The devices also provide no indication of alarm to alert operating room associates of the excessive nature of blood loss nor do the devices provide manual access to the addition of other secured surgical items such as smaller needles or sponges, nor do the other devices provide fluid balance status. The prior art also provides no printer or other tangible record of transactions during surgery for entry in the permanent record on the patient's chart.